Treatment resistant schizophrenia: Clinical, biological, and therapeutic perspectives

Elevated serum IGFBP-1 levels correlate with cognitive deficits in treatment-resistant and chronic medicated schizophrenia patients

BACKGROUND

Schizophrenia is a debilitating psychiatric disorder with diverse cognitive impairments. Insulin-like growth factor binding protein 1 (IGFBP-1), a ubiquitous negative regulator of IGF signaling, crosses the blood-brain barrier after peripheral synthesis. Given the crucial role of IGF signaling in cognitive function, we reasoned that altered serum IGFBP-1 concentrations might be associated with cognitive impairments in schizophrenia. To test this hypothesis, we examined the relationship between serum IGFBP-1 levels and cognitive performance in both medicated and treatment-resistant schizophrenia (TRS) patients.

METHODS

Serum IGFBP-1 was measured in 31 TRS patients, 49 chronic medicated schizophrenia (CMS) patients, and 53 healthy controls. Clinical symptom severity was evaluated using the Positive and Negative Syndrome Scale (PANSS) and cognitive functions using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

RESULTS

Both TRS and CMS patients exhibited cognitive deficits compared to healthy controls (p < 0.05). Serum IGFBP-1 concentration differed significantly among groups (F=36.805, p < 0.001) and post hoc tests demonstrated significantly higher concentrations in both schizophrenia groups compared to controls (p < 0.001). Further, serum IGFBP-1 concentration was higher in the TRS group than the CMS group (p = 0.048). Correlation analysis identified a significant relationship between serum IGFBP-1 and attention in the TRS group (r = 0.411, p = 0.021), immediate memory in the CMS group (r = -0.417, p = 0.003), and RBANS total score in the CMS group (r = -0.368, p = 0.009). Multiple regression analysis adjusting for confounding factors revealed that serum IGFBP-1 was independently associated with attention in TRS patients (p = 0.016, 95 %CI. 0.002-0.015) and immediate memory in CMS patients (p = 0.022, 95 %CI-0.012 to -0.001).

CONCLUSIONS

Elevated serum IGFBP-1 concentration may serve as a predictive biomarker for distinct cognitive deficits in TRS and CMS patients. Further investigations are warranted.

Smoking as a mediator in the association between major depressive disorder and schizophrenia on lung cancer risk: a bidirectional/multivariable and mediation Mendelian randomization study

Background & Aims

Major depressive disorder and schizophrenia have been hypothesized to be closely associated with cancer. However, the associations between these psychiatric conditions and the development of lung cancer remain uncertain. This study aimed to explore the causal relationship among major depressive disorder, schizophrenia, and the risk of lung cancer.

Methods

Two-sample bidirectional/multivariable and mediation Mendelian randomization (MR) analyses were conducted. Genome-wide summary data on major depressive disorder (N=500,199) and schizophrenia (N=127,906) were utilized. Data on the risk of lung cancer (overall, adenocarcinoma, and squamous cell) were collected from a cohort of individuals of European ancestry (N=27,209). Three smoking-related behaviors (smoking initiation, pack years of smoking, and cigarettes smoked per day) were included in the multivariable and mediation MR analyses.

Results

Patients with schizophrenia had a significantly greater risk of developing lung cancer (odds ratio (OR) = 1.144, 95% confidence interval (95% CI): 1.048-1.248, P = 0.003). The number of cigarettes smoked per day partially mediated the relationship between schizophrenia and the overall risk of lung cancer (OR = 1.185, 95% CI: 1.112-1.264, P = 0.021, proportion of mediation effect: 61.033%). However, there is no reliable evidence indicating an association between major depressive disorder and the risk of lung cancer (overall, adenocarcinoma, and squamous cell cancer).

Conclusions

The findings indicated an association between schizophrenia and an increased risk of lung cancer, with smoking served as a partial mediator. When smoking was included in the regression analysis, the explanatory power of schizophrenia diagnosis was reduced, suggesting that smoking may be an important causal contributor to lung cancer in this population. Given the high prevalence of smoking among individuals with schizophrenia, these results underscore the need for further research to explore the underlying mechanisms of smoking's impact. Consequently, greater emphasis should be placed on monitoring the respiratory health of individuals with schizophrenia and implementing early interventions to address smoking-related behaviors.

Correlations between Immunoinflammatory Factor Levels and Cognitive Functions and Brain Structural Magnetic Resonance Imaging Features among Patients with Primary Schizophrenia

BACKGROUND

Schizophrenia is associated with significant cognitive impairment. However, the pathophysiological mechanisms underlying cognitive dysfunction in schizophrenia remain unclear. Based on the latest concept of cognition, immunoinflammatory factors and structural magnetic resonance imaging (sMRI) features of the brain are considered markers of schizophrenia. This study explored the correlations between cognitive function and immunoinflammatory factors and sMRI in primary schizophrenia patients.

METHODS

Non-interventional cross-sectional study was conducted, including 21 patients with primary schizophrenia, who were identified based on the Diagnostic and Statistical Manual, Fifth Edition (DSM-V) and grouped under the observation group. Thirty healthy volunteers with age, gender, hand dominance, and education duration matched with those of the primary schizophrenia patients were recruited to the control group. All subjects underwent sMRI examination. MATRICS consensus cognitive battery (MCCB) was employed to assess the cognitive functions among patients with primary schizophrenia. The levels of serum amyloid A (SAA), monocyte chemoattractant protein 1 (MCP-1), and chitinase-3-like protein 1 (YKL-40) were measured by means of enzyme-linked immunosorbent assay (ELISA). Pearson's correlation analysis was carried out to analyze the correlation between immunoinflammatory factor levels and cognitive functions as well as brain sMRI features.

RESULTS

The scores for all MCCB items and the total score for the observation group were apparently lower than those for the control group (p < 0.001), while the YKL-40 and SAA levels were notably higher in the observation group (t = 3.406, p < 0.05; t = 5.656, p < 0.001). Compared to the control group, the observation group exhibited reduced volumes of left and right insular lobes, left and right anterior cingulate cortexes, left and right hippocampi, right parahippocampal gyrus, right amygdala, left inferior occipital lobe, left superior temporal lobe, left temporal pole, and left middle and inferior temporal lobes (p < 0.001). The levels of YKL-40 and SAA were both negatively correlated with MCCB score (r = -0.3668, p = 0.004; r = -0.8495, p < 0.001). The volumes of right insular lobe, left and right anterior cingulate cortexes, right parahippocampal gyrus, right amygdala, and gray matter in left middle temporal lobe were all negatively correlated with the levels of YKL-40 and SAA (p < 0.05).

CONCLUSION

Cognitive impairment in patients with primary schizophrenia is associated with increased serum SAA and YKL-40 levels and decreased gray matter volume.

Electrophysiological Markers Predicting Antipsychotic Treatment Response in Patients with Schizophrenia: A Retrospective Study

Purpose

This study aimed to provide an objective means of predicting treatment responses in patients with schizophrenia using quantitative electroencephalography (qEEG) as an electrophysiological indicator. We obtained qEEG recordings from patients with schizophrenia and explored them for patterns indicative of treatment responsiveness.

Patients and Methods

The study included 68 patients had been diagnosed with schizophrenia spectrum disorder. After retrospectively gathering demographic information, clinical data such as qEEG, Positive and Negative Syndrome Scale (PANSS), a multiple regression analysis was performed. This analysis employed baseline qEEG findings as independent variables and PANSS score changes as dependent variables to discern causal relationships.

Results

The mean age of the participants was 38.4 years(SD =13.73). The mean PANSS score on admission was 92.97, decreasing to 67.41 at discharge. Multiple regression analysis revealed that delta waves in T4 (β=0.346, t=3.165, p=0.002), and high-beta waves in Fp2 (β=0.231, t=2.361, p=0.021) were associated with PANSS changes in absolute power. In addition, the delta waves of O2 (β=0.250, t=3.288, p=0.002); beta waves of T3 (β=-1.463, t=-5.423, p<0.001) and O2 (β=0.551, t=3.366, p=0.001); high beta waves of Fp1 (β=0.307, t=4.026, p<0.001), T3 (β=0.855, t=4.414, p<0.001) and T6 (β=-0.838, t=-4.559, p<0.001) of absolute power using the Z-score were also related to PANSS changes. Pearson's correlation analysis showed that only delta waves at Cz (r= 0.246, p=0.043) in absolute power correlated with changes in the PANSS.

Conclusion

We found that certain qEEG wave patterns in patients with schizophrenia prior to antipsychotic treatment were linked to PANSS changes before and after treatment. Delta waves and beta waves, primarily in the frontal and temporal regions, were found to be significantly associated with changes in PANSS scores. In the future, the qEEG indicators identified in this study could serve as electrophysiological markers for predicting antipsychotic treatment responses in patients with schizophrenia.

Successful utilization of clozapine for a patient with treatment-resistant schizophrenia after recurrent violent behavior

BACKGROUND

In patients with schizophrenia, violent behavior is a clinically important factor that prevents their discharge. Clozapine is an effective antipsychotic medication for treatment-resistant schizophrenia, and its usefulness for aggressive behavior has also been suggested.

CASE PRESENTATION

We present the case of a 38-year-old male patient diagnosed with schizophrenia who was successfully treated with clozapine after recurrent violent behavior. He was diagnosed with schizophrenia during his adolescence. He was hospitalized for treatment in his teens, but his hallucinations and delusions persisted even after discharge. In his 30s, he became noticeably emotionally unstable, and despite being treated for an adequate period with sufficient doses of several antipsychotics, his symptoms did not improve. This led to repeated hospitalizations triggered by violent behavior toward his parents and siblings within the home. During his fourth hospitalization, clozapine was initiated due to multiple incidents of violence toward nursing staff secondary to hallucinations and delusions. As the dose of clozapine was gradually increased with therapeutic drug monitoring, the patient's hostility, uncooperativeness, and suspiciousness markedly improved, and his aggressive behavior disappeared. He was discharged to a facility on day 194 after starting clozapine and has continued outpatient visits.

CONCLUSION

Clozapine was suggested to be effective for aggressive behavior in patients with treatment-resistant schizophrenia and should be actively considered. In such cases, regular measurement of blood concentration is useful for adjusting the dosage of clozapine.

Lactate: a prospective target for therapeutic intervention in psychiatric disease

ABSTRACT

Although antipsychotics that act via monoaminergic neurotransmitter modulation have considerable therapeutic effect, they cannot completely relieve clinical symptoms in patients suffering from psychiatric disorders. This may be attributed to the limited range of neurotransmitters that are regulated by psychotropic drugs. Recent findings indicate the need for investigation of psychotropic medications that target less-studied neurotransmitters. Among these candidate neurotransmitters, lactate is developing from being a waste metabolite to a glial-neuronal signaling molecule in recent years. Previous studies have suggested that cerebral lactate levels change considerably in numerous psychiatric illnesses; animal experiments have also shown that the supply of exogenous lactate exerts an antidepressant effect. In this review, we have described how medications targeting newer neurotransmitters offer promise in psychiatric diseases; we have also summarized the advances in the use of lactate (and its corresponding signaling pathways) as a signaling molecule. In addition, we have described the alterations in brain lactate levels in depression, anxiety, bipolar disorder, and schizophrenia and have indicated the challenges that need to be overcome before brain lactate can be used as a therapeutic target in psychopharmacology.

Elevated intrinsic cortical curvature in treatment-resistant schizophrenia: Evidence of structural deformation in functional connectivity areas and comparison with alternate indices of structure

BACKGROUND

Research suggests structural and connectivity abnormalities in patients with treatment-resistant schizophrenia (TRS) compared to first-line responders and healthy-controls. However, measures of these abnormalities are often influenced by external factors like nicotine and antipsychotics, limiting their clinical utility. Intrinsic-cortical-curvature (ICC) presents a millimetre-scale measure of brain gyrification, highly sensitive to schizophrenia differences, and associated with TRS-like traits in early stages of the disorder. Despite this evidence, ICC in TRS remains unexplored. This study investigates ICC as a marker for treatment resistance in TRS, alongside structural indices for comparison.

METHODS

We assessed ICC in anterior cingulate, dorsolateral prefrontal, temporal, and parietal cortices of 38 first-line responders, 30 clozapine-resistant TRS, 37 clozapine-responsive TRS, and 52 healthy-controls. For comparative purposes, Fold and Curvature indices were also analyzed.

RESULTS

Adjusting for age, sex, nicotine-use, and chlorpromazine equivalence, principal findings indicate ICC elevations in the left hemisphere dorsolateral prefrontal (p < 0.001, η2partial = 0.142) and temporal cortices (LH p = 0.007, η2partial = 0.060; RH p = 0.011, η2partial = 0.076) of both TRS groups, and left anterior cingulate cortex of clozapine-resistant TRS (p = 0.026, η2partial = 0.065), compared to healthy-controls. Elevations that correlated with reduced cognition (p = 0.001) and negative symptomology (p < 0.034) in clozapine-resistant TRS. Fold and Curvature indices only detected group differences in the right parietal cortex, showing interactions with age, sex, and nicotine use. ICC showed interactions with age.

CONCLUSION

ICC elevations were found among patients with TRS, and correlated with symptom severity. ICCs relative independence from sex, nicotine-use, and antipsychotics, may support ICC's potential as a viable marker for TRS, though age interactions should be considered.

Current Findings and Potential Mechanisms of KarXT (Xanomeline-Trospium) in Schizophrenia Treatment

Standard schizophrenia treatment involves antipsychotic medications that target D2 dopamine receptors. However, these drugs have limitations in addressing all symptoms and can lead to adverse effects such as motor impairments, metabolic effects, sedation, sexual dysfunction, cognitive impairment, and tardive dyskinesia. Recently, KarXT has emerged as a novel drug for schizophrenia. KarXT combines xanomeline, a muscarinic receptor M1 and M4 agonist, with trospium, a nonselective antimuscarinic agent. Of note, xanomeline can readily cross blood-brain barrier (BBB) and, thus, enter into the brain, thereby stimulating muscarinic receptors (M1 and M4). By doing so, xanomeline has been shown to target negative symptoms and potentially improve positive symptoms. Trospium, on the other hand, is not able to cross BBB, thereby not affecting M1 and M4 receptors; instead, it acts as an antimuscarinic agent and, hence, diminishes peripheral activity of muscarinic receptors to minimize side effects probably stemming from xanomeline in other organs. Accordingly, ongoing clinical trials investigating KarXT's efficacy in schizophrenia have demonstrated positive outcomes, including significant improvements in the Positive and Negative Syndrome Scale (PANSS) total score and cognitive function compared with placebo. These findings emphasize the potential of KarXT as a promising treatment for schizophrenia, providing symptom relief while minimizing side effects associated with xanomeline monotherapy. Despite such promising evidence, further research is needed to confirm the efficacy, safety, and tolerability of KarXT in managing schizophrenia. This review article explores the current findings and potential mechanisms of KarXT in the treatment of schizophrenia.

The Relationship between Sense of Presence, Emotional Response, and Clinical Outcomes in Virtual Reality-Based Therapy for Treatment-Resistant Schizophrenia: An Exploratory Correlational Study

Avatar therapy (AT) is a novel virtual reality-based psychotherapy that has been developed to treat auditory verbal hallucinations (AVH) in treatment-resistant schizophrenia. Various psychotherapeutic components, such as emotions and sense of presence, could contribute to clinical outcomes. However, the interplay between sense of presence, emotions, and clinical response has seldom been investigated. This study aimed to explore the relations between sense of presence, emotions, and clinical outcomes in AT. To conduct this investigation, data from previous and ongoing AT trials were used. Sense of presence and emotions were assessed using standardized questionnaires. AVH were evaluated using the Psychotic Symptom Rating Scales. While sense of presence was positively associated with positive emotions such as control and serenity, no significant associations were found for negative emotions. Moreover, a higher level of sense of presence was associated with a bigger decrease in AVH. Overall, positive emotions seem to be associated with sense of presence in AT. Sense of presence also seems to be involved in the therapeutic outcome, thereby suggesting that this could be an important component related to clinical response. More studies are needed to confirm these trends, which could be generalized to other virtual reality-based psychotherapies.

Therapeutic potential of gamma entrainment using sensory stimulation for cognitive symptoms associated with schizophrenia

Schizophrenia is a complex neuropsychiatric disorder with significant morbidity. Treatment options that address the spectrum of symptoms are limited, highlighting the need for innovative therapeutic approaches. Gamma Entrainment Using Sensory Stimulation (GENUS) is an emerging treatment for neuropsychiatric disorders that uses sensory stimulation to entrain impaired oscillatory network activity and restore brain function. Aberrant oscillatory activity often underlies the symptoms experienced by patients with schizophrenia. We propose that GENUS has therapeutic potential for schizophrenia. This paper reviews the current status of schizophrenia treatment and explores the use of sensory stimulation as an adjunctive treatment, specifically through gamma entrainment. Impaired gamma frequency entrainment is observed in patients, particularly in response to auditory and visual stimuli. Thus, sensory stimulation, such as music listening, may have therapeutic potential for individuals with schizophrenia. GENUS holds novel therapeutic potential to improve the lives of individuals with schizophrenia, but further research is required to determine the efficacy of GENUS, optimize its delivery and therapeutic window, and develop strategies for its implementation in specific patient populations.

Augmentation Strategies for Partial or Non-responders to Clozapine in Patients with Schizophrenia: A Bayesian Network Meta-analysis of Randomized Controlled Trials

Clozapine is the only approved drug for treatment-resistant schizophrenia, but the response to the drug is often inadequate. Augmentation with other antipsychotics, anticonvulsants, and antidepressants is recommended for such patients, but there is a lack of evidence regarding the most effective therapy. This network meta-analysis was conducted to evaluate the efficacy of pharmacological agents used in the augmentation strategies in patients who were partial/ non-responders to clozapine. Relevant data were extracted from 30 randomized controlled trials through searches of electronic databases (MEDLINE/PubMed, Embase, Cochrane, clinical trial registries). PRISMA guidelines were followed for the extraction, management, analysis, and reporting of the data. The outcome measure in this study was a reduction in symptom severity according to total PANSS/BPRS and was reported as the standardized mean difference with a 95% credible interval. Bayesian network meta-analysis with random effects model and uninformative priors was conducted, and the ranking probability of each intervention was done. Meta-regression was done to assess the effect of duration on the reduction in symptom severity scores. Mirtazapine (-5.2 [95%CrI: -7.7, -2.7]) and memantine (-2.1 [95%CrI: -4.0, -0.19]] were more efficacious than placebo for augmentation of clozapine in partial/non-responders and were the most effective adjunctive agents as per SUCRA scores. Both drugs did not cause a significant increase in frequency of adverse events compared to placebo. There was a significant effect of duration on the reduction in symptom severity. There was no evident publication bias. Mirtazapine and memantine may prove beneficial for augmentation of clozapine in non/partial responders to monotherapy.

Prevalence and risk factors for chronic kidney disease among older adult patients with schizophrenia in Taiwan

OBJECTIVES

There is an increasing incidence and prevalence of patients with chronic kidney disease (CKD) worldwide. Little is known the prevalence of CKD among older patients with schizophrenia. The purpose of this study was to investigate the prevalence of CKD and its risk factors in older adults with schizophrenia.

METHODS

In this cross-sectional study, a convenience sample of 240 patients with schizophrenia age 50 or older were recruited. In addition to demographic and clinical data, participants' estimated glomerular filtration rate was calculated using the Modification of Diet in Renal Disease equation based on age, sex, ethnicity, and serum creatinine level determined from a blood sample taken from participants.

RESULTS

The overall prevalence of CKD was 11.3%. Those with CKD group were older, had a longer duration of psychiatric illness, a higher body mass index (BMI), and diagnoses of hypertension compared to those in the non-CKD group. Independent of other risk factors, older age and BMI were significantly associated with CKD.

CONCLUSIONS

This study found that the overall prevalence of CKD in older patients with schizophrenia was 11.3%. Risk factors for CKD in this population were older age and higher BMI. In addition to early identification and early treatment of CKD in older patients with schizophrenia, clinicians should actively manage the risk factors identified in this study, such as higher BMI and older age.

Aberrant connectivity in the hippocampus, bilateral insula and temporal poles precedes treatment resistance in first-episode psychosis: a prospective resting-state functional magnetic resonance imaging study with connectivity concordance mapping

Functional connectivity resting-state functional magnetic resonance imaging has been proposed to predict antipsychotic treatment response in schizophrenia. However, only a few prospective studies have examined baseline resting-state functional magnetic resonance imaging data in drug-naïve first-episode schizophrenia patients with regard to subsequent treatment response. Data-driven approaches to conceptualize and measure functional connectivity patterns vary broadly, and model-free, voxel-wise, whole-brain analysis techniques are scarce. Here, we apply such a method, called connectivity concordance mapping to resting-state functional magnetic resonance imaging data acquired from an Asian sample (n = 60) with first-episode psychosis, prior to pharmaceutical treatment. Using a longitudinal design, 12 months after the resting-state functional magnetic resonance imaging, we measured and classified patients into two groups based on psychometric testing: treatment responsive and treatment resistant. Next, we compared the two groups' connectivity concordance maps that were derived from the resting-state functional magnetic resonance imaging data at baseline. We have identified consistently higher functional connectivity in the treatment-resistant group in a network including the left hippocampus, bilateral insula and temporal poles. These data-driven novel findings can help researchers to consider new regions of interest and facilitate biomarker development in order to identify treatment-resistant schizophrenia patients early, in advance of treatment and at the time of their first psychotic episode.

Effects of the PAM of mGluR2, JNJ-46356479, on brain apoptotic protein levels in a mouse model of schizophrenia

Current treatment for schizophrenia (SZ) ameliorates the positive symptoms, but is inefficient in treating the negative and cognitive symptoms. The SZ glutamatergic dysfunction hypothesis has opened new avenues in the development of novel drugs targeting the glutamate storm, an inducer of progressive neuropathological changes. Positive allosteric modulators of metabotropic glutamate receptor 2 (mGluR2), such as JNJ-46356479 (JNJ), reduce the presynaptic release of glutamate, which has previously been demonstrated to attenuate glutamate- and dopamine-induced apoptosis in human neuroblastoma cell cultures. We hypothesised that JNJ treatment would modify the brain levels of apoptotic proteins in a mouse model of ketamine (KET)-induced schizophrenia. We analysed the levels of proapoptotic (caspase-3 and Bax) and antiapoptotic (Bcl-2) proteins by western blot in the prefrontal cortex and hippocampus of JNJ-treated mice. JNJ attenuated apoptosis in the brain by partially restoring the levels of the antiapoptotic Bcl-2 protein, which is significantly reduced in animals exposed to KET. Additionally, a significant inverse correlation was observed between proapoptotic protein levels and behavioural deficits in the mice. Our findings suggest that JNJ may attenuate brain apoptosis in vivo, as previously described in cell cultures, providing a link between neuropathological deficits and SZ symptomatology.

Association of cytokines levels, psychopathology and cognition among CR-TRS patients with metabolic syndrome

Clozapine-resistant treatment-refractory schizophrenia (CR-TRS) patients face significant clinical challenges. While links between metabolic syndrome (MetS) and inflammatory cytokines in schizophrenia have been established, the relationship between MetS and cytokine levels in CR-TRS patients remains unexplored. This study aimed to investigate the relationship between cytokines levels, clinical symptoms and cognitive impairments in CR-TRS patients, both with and without MetS. The study included 69 CR-TRS patients (31with MetS and 38 without MetS) and 84 healthy controls. The levels of IL-2, IL-6, TNF-α and routine biochemical parameters were measured. Psychopathological symptoms and cognitive function were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), respectively. We found that CR-TRS patients with MetS displayed lower cognitive function scores compared to those without MetS, even when accounting for potential confounders. TNF-α levels were significantly higher in CRTRS patients with MetS compared to those without MetS, demonstrating substantial pathophysiological potential for CR-TRS patients with MetS via receiver operating characteristic curve (ROC). In CR-TRS patients without MetS, IL-2 independently contributed to the total score and general psychopathology subscore of PANSS. Additionally, IL-6 exhibited an independent contribution to the positive subscore of PANSS. In terms of cognition function, IL-6 independently contributed to the delayed memory of RBANS in CR-TRS patients without MetS. TNF-α could potentially serve as a predictive marker for distinguishing between CR-TRS patients with/without MetS, while IL-2 and IL-6 could independently contribute to psychopathological symptoms or cognitive function in CRTRS patients without MetS. Our study provided insights into the potential interplay between cytokines, clinical symptoms and cognitive impairments in CR-TRS patients with/without MetS.

Variations to plasma H2O2 levels and TAC in chronical medicated and treatment-resistant male schizophrenia patients: Correlations with psychopathology

Accumulating evidence suggests that imbalanced oxidative stress (OS) may contribute to the mechanism of schizophrenia. The aim of the present study was to evaluate the associations of OS parameters with psychopathological symptoms in male chronically medicated schizophrenia (CMS) and treatment-resistant schizophrenia (TRS) patients. Levels of hydrogen peroxide (H2O2), hydroxyl radical (·OH), peroxidase (POD), α-tocopherol (α-toc), total antioxidant capacity (TAC), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinases-1 (TIMP-1) were assayed in males with CMS and TRS, and matched healthy controls. Schizophrenia symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). The results demonstrated significant differences in the variables H2O2 (F = 5.068, p = 0.008), ·OH (F = 31.856, p < 0.001), POD (F = 14.043, p < 0.001), α-toc (F = 3.711, p = 0.027), TAC (F = 24.098, p < 0.001), and MMP-9 (F = 3.219, p = 0.043) between TRS and CMS patients and healthy controls. For TRS patients, H2O2 levels were correlated to the PANSS positive subscale (r = 0.386, p = 0.032) and smoking (r = -0,412, p = 0.021), while TAC was significantly negatively correlated to the PANSS total score (r = -0.578, p = 0.001) and POD and TAC levels were positively correlated to body mass index (r = 0.412 and 0.357, p = 0.021 and 0.049, respectively). For patients with CMS, ·OH levels and TAC were positively correlated to the PANSS general subscale (r = 0.308, p = 0.031) and negatively correlated to the PANSS total score (r = -0.543, p < 0.001). Furthermore, H2O2, α-toc, and ·OH may be protective factors against TRS, and POD was a risk factor. Patients with CMS and TRS exhibit an imbalance in OS, thus warranting future investigations.

Neuroanatomical comparison of treatment-resistant and treatment-responsive schizophrenia patients using the cloud-based brain magnetic resonance image segmentation and parcellation system: An MRIcloud study

Recent developments in neuroimaging have improved our understanding of the biological mechanisms underlying schizophrenia. However, neuroimaging findings in treatment-resistant schizophrenia (TRS) remain unclear. In the present study, we aimed to explore potential neuroanatomical regions that may be associated with treatment resistance in schizophrenia patients by comparing neuroanatomical regions of TRS and non-TRS patients using the MRICloud method. A total of 33 schizophrenia patients (meeting DSM 5 diagnostic criteria for schizophrenia) were included in the study. Patients were dichotomized into TRS (n = 18) and non-TRS (n = 15) groups, and all patients underwent MRI. Neuroanatomical regions of TRS and non-TRS patients were compared using the MRICloud method. Disease severity was measured using the Positive and Negative Syndrome Scale (PANSS). Interestingly, a statistically significant greater left Corpus Collosum (CC) thickness was found in TRS patients compared to non-TRS patients. It is clear that further studies comparing TRS patients with non-TRS patients are needed, and these studies should focus on the circuits in the corpus callosum that are thought to play a role in treatment resistance. Further longitudinal studies are also needed to complement the cross-sectional studies, using a multimodal imaging approach in the patients with clearly defined TRS criteria.

Delusional infestation treated with risperidone: a series of 27 patients

BACKGROUND

Patients with delusional infestation (DI) frequently refuse to be treated with psychoactive drugs. In the past, pimozide was commonly used as a first-line agent but is now prescribed more rarely. Risperidone was first used to treat DI in 1995. A recent review identified 12 studies that evaluated the use of risperidone in 43 patients with DI.

OBJECTIVES

To study the characteristics of and therapeutic results in patients with DI treated with risperidone at a university medical centre in São Paulo, Brazil.

METHODS

We performed a retrospective study of patients with DI treated with risperidone at a dermatological university clinic since 2016. Records were reviewed for personal data and findings related to treatment.

RESULTS

Twenty-seven patients were studied (20 women and 7 men). The maintenance dose of risperidone varied from 1 mg three times weekly to 8 mg daily. Control of symptoms was achieved in the majority of patients. A reduction in dosage due to side-effects was seen in four patients; risperidone had to be switched to another antipsychotic in three cases, despite a good response. Only one patient did not respond to risperidone.

CONCLUSIONS

Risperidone is an effective, well-tolerated and safe treatment for delusional parasitosis. Adequate follow-up is mandatory in order to obtain long-term control of symptoms.

The mediodorsal thalamus in executive control

Executive control, the ability to organize thoughts and action plans in real time, is a defining feature of higher cognition. Classical theories have emphasized cortical contributions to this process, but recent studies have reinvigorated interest in the role of the thalamus. Although it is well established that local thalamic damage diminishes cognitive capacity, such observations have been difficult to inform functional models. Recent progress in experimental techniques is beginning to enrich our understanding of the anatomical, physiological, and computational substrates underlying thalamic engagement in executive control. In this review, we discuss this progress and particularly focus on the mediodorsal thalamus, which regulates the activity within and across frontal cortical areas. We end with a synthesis that highlights frontal thalamocortical interactions in cognitive computations and discusses its functional implications in normal and pathological conditions.

Mendelian randomization study of the relationship between blood and urine biomarkers and schizophrenia in the UK Biobank cohort

BACKGROUND

The identification of suitable biomarkers is of crucial clinical importance for the early diagnosis of treatment-resistant schizophrenia (TRS). This study aims to comprehensively analyze the association between TRS and blood and urine biomarkers.

METHODS

Candidate TRS-related single nucleotide polymorphisms (SNPs) were obtained from a recent genome-wide association study. The UK Biobank cohort, comprising 376,807 subjects with blood and urine biomarker testing data, was used to calculate the polygenic risk score (PRS) for TRS. Pearson correlation analyses were performed to evaluate the correlation between TRS PRS and each of the biomarkers, using calculated TRS PRS as the instrumental variables. Bidirectional two-sample Mendelian randomization (MR) was used to assess potential causal associations between candidate biomarkers with TRS.

RESULTS

Here we identify a significant association between TRS PRS and phosphate (r = 0.007, P = 1.96 × 10-4). Sex subgroup analyses identify seven and three candidate biomarkers associated with TRS PRS in male and female participants, respectively. For example, total protein and phosphate for males, creatinine and phosphate for females. Bidirectional two-sample MR analyses indicate that TRS is negatively associated with cholesterol (estimate = -0.363, P  = 0.008). Conversely, TRS is positively associated with total protein (estimate = 0.137, P  = 0.027), mean corpuscular volume (estimate = 0.032, P  = 2.25 × 10-5), and mean corpuscular hemoglobin (estimate = 0.018, P  = 0.007).

CONCLUSIONS

Our findings provide insights into the roles of blood and urine biomarkers in the early detection and treatment of TRS.

Role of the immune-kynurenine pathway in treatment-resistant schizophrenia

BACKGROUND

The immune-inflammatory response system (IRS) and kynurenine pathway (KP) have been implicated in the pathophysiology of schizophrenia. Studies have shown inflammation-related effects on KP metabolism in patients with schizophrenia. This study investigated the relationship between KP metabolites, IRS, and the compensatory immune-regulatory reflex system (CIRS) in patients with treatment-resistant schizophrenia (TRS).

METHODS

Patients with (n = 53) and without TRS (n = 47), and healthy controls (HCs, n = 49) were enrolled. We quantified plasma levels of pro-inflammatory cytokines (interleukin [IL]-1β, IL-2, IL-6, soluble(s)IL-6 receptor, IL-8, IL-12, IL-17, IL-18, interferon-γ, and tumor necrosis factor[TNF]-α) and anti-inflammatory cytokines (IL-1 receptor antagonist, IL-4, IL-10, tumor growth factor [TGF]-β1, TGF-β2, soluble (s) IL-2 receptor subunit α, sIL-2 receptor subunit β, and sTNF-α receptor 1) and calculated the IRS/CIRS ratio. We also tested serum metabolites of the KP, including kynurenine (KYN), kynurenic acid (KYNA), and quinolinic acid (QUIN), along with the QUIN/KYNA ratio.

RESULTS

Patients with TRS had significantly higher IRS/CIRS ratio than non-TRS patients (p = 0.002) and HCs (p = 0.007), and significantly lower KYN (p = 0.001) and KYNA (p = 0.01) levels than HCs. Binary logistic regression analysis revealed that a younger age at illness onset (odds ratio [OR] = 0.91, p = 0.02) and a higher IRS/CIRS ratio (OR = 1.22; p = 0.007) were risk factors for patients with TRS. After further adjusted for age of onset, the QUIN/KYNA ratio (β = 0.97; p = 0.02) significantly moderated the relationship between IRS/CIRS and TRS, showing that in the higher QUIN/KYNA condition, higher IRS/CIRS ratio were significantly and more likely to be associated with patients with TRS (β = 0.12, z = 3.19, p = 0.001), whereas in the low QUIN/KYNA condition, the association between IRS/CIRS ratio and TRS was weak and insignificant.

CONCLUSIONS

The peripheral immune response was imbalanced in TRS and was preferentially directed towards the IRS compared to patients without TRS and healthy controls, which is likely to play a role in neurotoxicity. Additionally, peripheral KP activation was also imbalanced, as evidenced by significantly reduced KYN and KYNA levels in patients with TRS compared to healthy controls, but none of KP metabolisms were significantly difference in non-TRS patients compared to healthy controls. QUIN/KYNA ratio involving to the degree of activation of NMDA receptors, indicated the neurotoxic level of the KP activation. The interaction between IRS/CIRS and QUIN/KYNA ratio was significant in predicting TRS, and our findings suggest a potential role for the immune-kynurenine pathway in TRS pathogenesis.

Radix Bupleuri aqueous extract attenuates MK801-induced schizophrenia-like symptoms in mice: Participation of intestinal flora

Schizophrenia (SCZ) is a psychotic mental disorder characterized by cognitive, behavioral, and social impairments. However, current pharmacological treatment regimens are subpar in terms of effectiveness. This study aimed to investigate the function of Radix Bupleuri aqueous extract in SCZ in mouse models. The SCZ mouse model was established by MK-801 injection and feeding of Radix Bupleuri aqueous extract or combined antibiotics. Radix Bupleuri aqueous extract significantly improved the aberrant behaviors and neuronal damage in SCZ mice, upregulated SYP and PSD-95 expression and BDNF levels in hippocampal homogenates, down-regulated DA and 5-HT levels, and suppressed microglial activation in SCZ mice. Moreover, Radix Bupleuri aqueous extract improved the integrity of the intestinal tract barrier. The 16 S rRNA sequencing of feces showed that Radix Bupleuri extract modulated the composition of gut flora. Lactobacillus abundance was decreased in SCZ mice and reversed by Radix Bupleuri aqueous extract administration which exhibited a significant negative correlation with IL-6, IL-1β, DA, and 5-HT, and a significant positive correlation with BDNF levels in hippocampal tissues. The abundance of Parabacteroides and Alloprevotella was increased in SCZ mice. It was reversed by Radix Bupleuri aqueous extract administration, which exhibited a positive correlation with IL-6, IL-1β, and 5-HT and a negative correlation with BDNF. In conclusion, Radix Bupleuri aqueous extract attenuates the inflammatory response in hippocampal tissues and modulates neurotransmitter levels, exerting its neuroprotective effect in SCZ. Meanwhile, the alteration of intestinal flora may be involved in this process, which is expected to be an underlying therapeutic option in treating SCZ.

Association between elevated serum matrix metalloproteinase-2 and tumor necrosis factor-α, and clinical symptoms in male patients with treatment-resistant and chronic medicated schizophrenia

BACKGROUND

Inflammation has an important role in the pathogenesis of schizophrenia. The aim of this study was to investigate the levels of tumor necrosis factor (TNF) and matrix metalloproteinase-2 (MMP-2) in male patients with treatment-resistant schizophrenia (TRS) and chronic medicated schizophrenia (CMS), and the relationship with psychopathology.

METHODS

The study enrolled 31 TRS and 49 cm male patients, and 53 healthy controls. Serum MMP-2 and TNF-α levels were measured by the Luminex liquid suspension chip detection method. Positive and Negative Syndrome Scale (PANSS) scores were used to evaluate symptom severity and Repeatable Battery for the Assessment of Neuropsychological Status was used to assess cognitive function.

RESULTS

Serum TNF-α and MMP-2 levels differed significantly between TRS, CMS and healthy control patients (F = 4.289, P = 0.016; F = 4.682, P = 0.011, respectively). Bonferroni correction demonstrated that serum TNF-α levels were significantly elevated in CMS patients (P = 0.022) and MMP-2 levels were significantly higher in TRS patients (P = 0.014) compared to healthy controls. In TRS patients, TNF-α was negatively correlated with age (r=-0.435, P = 0.015) and age of onset (r=-0.409, P = 0.022). In CMS patients, MMP-2 and TNF-α were negatively correlated with PANSS negative and total scores, and TNF-α was negatively correlated with PANSS general psychopathology scores (all P < 0.05). MMP-2 levels were positively correlated with TNF-α levels (P < 0.05), but not with cognitive function (P > 0.05).

CONCLUSION

The results indicate the involvement of inflammation in the etiology of TRS and CMS. Further studies are warranted.

Gene expression imputation provides clinical and biological insights into treatment-resistant schizophrenia polygenic risk

Genome-wide association studies (GWAS) have revealed the polygenic nature of treatment-resistant schizophrenia TRS. Gene expression imputation allowed the translation of GWAS results into regulatory mechanisms and the construction of gene expression (GReX) risk scores (GReX-RS).  In the present study we computed GReX-RS from the largest GWAS of TRS to assess its association with clinical features. We perform transcriptome imputation in the largest GWAS of TRS to find GReX associated with TRS using brain tissues. Then, for each tissue, we constructed a GReX-RS of the identified genes in a sample of 254 genotyped first episode of psychosis (FEP) patients to test its association with clinical phenotypes, including clinical symptomatology, global functioning and cognitive performance. Our analysis provides evidence that the polygenic basis of TRS includes genetic variants that modulate the expression of certain genes in certain brain areas (substantia nigra, hippocampus, amygdala and frontal cortex), which at the same time are related to clinical features in FEP patients, mainly persistence of negative symptoms and cognitive alterations in sustained attention, which have also been suggested as clinical predictors of TRS. Our results provide a clinical explanation of the polygenic architecture of TRS and give more insight into the biological mechanisms underlying TRS.

The 3-hit animal models of schizophrenia: Improving strategy to decipher and treat the disease?

Schizophrenia is a complex disease related to combination and interactions between genetic and environmental factors, with an epigenetic influence. After the development of the first mono-factorial animal models of schizophrenia (1-hit), that reproduced patterns of either positive, negative and/or cognitive symptoms, more complex models combining two factors (2-hit) have been developed to better fit with the multifactorial etiology of the disease. In the two past decades, a new way to design animal models of schizophrenia have emerged by adding a third hit (3-hit). This review aims to discuss the relevance of the risk factors chosen for the tuning of the 3-hit animal models, as well as the validities measurements and their contribution to schizophrenia understanding. We intended to establish a comprehensive overview to help in the choice of factors for the design of multiple-hit animal models of schizophrenia.

Uric acid is negatively associated with cognition in the first- episode of schizophrenia

BACKGROUND

We explored the relationship between levels of serum uric acid (UA) and cognitive impairment in people with schizophrenia to order to better protect and improve cognitive function in such patients.

METHODS

A uricase method evaluated serum UA levels in 82 individuals with first-episode schizophrenia and in 39 healthy controls. The Brief Psychiatric Rating Scale (BPRS) and the event-related potential P300 were used to assess the patient's psychiatric symptoms and cognitive functioning. The link between serum UA levels, BPRS scores, and P300 was investigated.

RESULTS

Prior to treatment, serum UA levels and latency N3 in the study group were significantly higher than in the control group, whereas the amplitude P3 was considerably lower. After therapy, the study group's BPRS scores, serum UA levels, latency N3, and amplitude P3 were lower than before treatment. According to correlation analysis, serum UA levels in the pre-treatment study group significantly positively correlated with BPRS score and latency N3 but not amplitude P3. After therapy, serum UA levels were no longer substantially related to the BPRS score or amplitude P3 but strongly and positively correlated with latency N3.

CONCLUSIONS

First-episode schizophrenia patients have higher serum UA levels than the general population which partly reflects poor cognitive performance. Improving patients' cognitive function may be facilitated by lowering serum UA levels.

The kynurenine pathway in treatment-resistant schizophrenia at the crossroads between pathophysiology and pharmacotherapy

Two cardinal elements in the complex and multifaceted pathophysiology of schizophrenia (SCZ) are neuroinflammation and dysregulation of glutamatergic neurotransmission, with the latter being especially involved in treatment-resistant schizophrenia (TRS). Interestingly, the Kynurenine (KYN) pathway (KP) is at the crossroad between them, constituting a potential causal link and a therapeutic target. Although there is preclinical and clinical evidence indicating a dysregulation of KP associated with the clinical phenotype of SCZ, clinical studies investigating the possible relationship between changes in biomarkers of the KP and response to pharmacotherapy are still limited. Therefore, we have studied possible differences in the circulating levels of biomarkers of the metabolism of tryptophan along the KP in 43 responders to first-line treatments (FLR) and 32 TRS patients treated with clozapine, and their possible associations with psychopathology in the two subgroups. Plasma levels of KYN were significantly higher in TRS patients than in FLR patients, indicating a greater activation of KP. Furthermore, the levels of quinolinic (NMDA receptor agonist) and kynurenic acid (NMDA negative allosteric modulator) showed a negative and a positive correlation with several dimensions and the overall symptomatology in the whole sample and in FLR, but not in TRS, suggesting a putative modulating effect of clozapine elicited through the NMDA receptors. Despite the cross-sectional design of the study that prevents us from demonstrating causation, these findings show a significant relationship among circulating KP biomarkers, psychopathology, and response to pharmacotherapy in SCZ. Therefore, plasma KP biomarkers should be further investigated for developing personalized medicine approaches in SCZ.

Next-Generation Proteomics of Brain Extracellular Vesicles in Schizophrenia Provide New Clues on the Altered Molecular Connectome

Extracellular vesicles (EVs) are tiny membranous structures that mediate intercellular communication. The role(s) of these vesicles have been widely investigated in the context of neurological diseases; however, their potential implications in the neuropathology subjacent to human psychiatric disorders remain mostly unknown. Here, by using next-generation discovery-driven proteomics, we investigate the potential role(s) of brain EVs (bEVs) in schizophrenia (SZ) by analyzing these vesicles from the three post-mortem anatomical brain regions: the prefrontal cortex (PFC), hippocampus (HC), and caudate (CAU). The results obtained indicate that bEVs from SZ-affected brains contain region-specific proteins that are associated with abnormal GABAergic and glutamatergic transmission. Similarly, these vesicles from the analyzed regions were implicated in synaptic decay, abnormal brain immunity, neuron structural imbalances, and impaired cell homeostasis. Our findings also provide evidence, for the first time, that networks of molecular exchange (involving the PFC, HC, and CAU) are potentially active and mediated by EVs in non-diseased brains. Additionally, these bEV-mediated networks seem to have become partially reversed and largely disrupted in the brains of subjects affected by SZ. Taken as a whole, these results open the door to the uncovering of new biological markers and therapeutic targets, based on the compositions of bEVs, for the benefit of patients affected by SZ and related psychotic disorders.

Cariprazine augmentation of clozapine in schizophrenia-a retrospective chart review

The aim of our study was to evaluate the efficacy of cariprazine augmentation of clozapine in treatment-resistant schizophrenia in a retrospective chart review. Among 916 medical records of schizophrenia patients, we identified 12 individuals treated with a combination of those drugs for a duration of 3-60 weeks [median 32 (10-40)]. Clinical Global Impression-Improvement (CGI-I) scores were used to measure the treatment response between the introduction of cariprazine augmentation of clozapine and the last point of observation. The majority of the patients presented treatment response (9/12 patients, 75%) after 4-16 weeks of therapy [median 6 (4-12)]. Treatment was associated with the decrease in positive, negative, affective, and anxiety symptom severity, as well as improvement of patient global functioning. One patient discontinued the treatment due to side effects (akathisia), and two patients halted the therapy due to the exacerbation of psychotic symptoms. Our study presents a thorough clinical description of the largest number of treatment-resistant schizophrenia patients medicated using cariprazine augmentation of clozapine in a "real-world" setting. Our results suggest that the use of this combination may lead to the improvement in a broad range of symptoms of patients with this condition.

Alterations of serum neuropeptide levels and their relationship to cognitive impairment and psychopathology in male patients with chronic schizophrenia

Serum neuropeptide levels may be linked to schizophrenia (SCZ) pathogenesis. This study aims to examine the relation between five serum neuropeptide levels and the cognition of patients with treatment-resistant schizophrenia (TRS), chronic stable schizophrenia (CSS), and in healthy controls (HC). Three groups were assessed: 29 TRS and 48 CSS patients who were hospitalized in regional psychiatric hospitals, and 53 HC. After the above participants were enrolled, we examined the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the blood serum levels of α-melanocyte stimulating hormone (α-MSH), β-endorphin (BE), neurotensin (NT), oxytocin (OT) and substance.P (S.P). Psychiatric symptoms in patients with SCZ were assessed with the Positive and Negative Syndrome Scale. SCZ patients performed worse than HC in total score and all subscales of the RBANS. The levels of the above five serum neuropeptides were significantly higher in SCZ than in HC. The levels of OT and S.P were significantly higher in CSS than in TRS patients. The α-MSH levels in TRS patients were significantly and negatively correlated with the language scores of RBANS. However, the BE and NT levels in CSS patients were significantly and positively correlated with the visuospatial/constructional scores of RBANS. Moreover, the interaction effect of NT and BE levels was positively associated with the visuospatial/constructional scores of RBANS. Therefore, abnormally increased serum neuropeptide levels may be associated with the physiology of SCZ, and may cause cognitive impairment and psychiatric symptoms, especially in patients with TRS.

Improving outcome of treatment-resistant schizophrenia: effects of cognitive remediation therapy

Treatment-Resistant Schizophrenia (TRS) represents a main clinical issue, associated with worse psychopathological outcomes, a more disrupted neurobiological substrate, and poorer neurocognitive performance across several domains, especially in verbal abilities. If cognitive impairment is a major determinant of patients' functional outcomes and quality of life, targeting cognitive dysfunction becomes even more crucial in TRS patients in order to minimize cognitive and functional deterioration. However, although Cognitive Remediation Therapy (CRT) represents the best available tool to treat cognitive dysfunction in schizophrenia, specific evidence of its efficacy in TRS is lacking. Based on these premises, our study aimed at investigating possible differences in CRT outcomes in a sample of 150 patients with schizophrenia, stratified according to antipsychotic response (TRS vs. non-TRS). Subjects were assessed for neurocognition through Brief Assessment of Cognition in Schizophrenia (BACS) and the Wisconsin Card Sorting Test (WCST) at baseline and after CRT. As expected, we observed greater baseline impairment among TRS patients in BACS-Verbal Memory and WCST-Executive Functions. Repeated measures ANCOVAs showed significant within-group pre-/post-CRT differences in the above-mentioned domains, both among non-TRS and TRS subjects. However, after CRT, no differences were observed between groups. This is the first study to indicate that CRT represents a highly valuable resource for TRS patients, since it may be able to fill the cognitive gap between treatment response groups. Our finding further highlights the importance of early implementation of CRT in addition to pharmacotherapy to reduce the cognitive and functional burden associated with the disease, especially for TRS patients.

Pre-clinical indications of brain stimulation treatments for non-affective psychiatric disorders, a status update

Over the past two decades noninvasive brain stimulation (NIBS) techniques have emerged as powerful therapeutic options for a range of psychiatric and neurological disorders. NIBS are hypothesized to rebalance pathological brain networks thus reducing symptoms and improving functioning. This development has been fueled by controlled studies with increasing size and rigor aiming to characterize how treatments induce clinically effective change. Clinical trials of NIBS for specific indications have resulted in federal approval for unipolar depression, bipolar depression, smoking cessation, and obsessive-compulsive disorder in the United States, and several other indications worldwide. As a rapidly emerging field, there are numerous pre-clinical indications currently in development using a variety of electrical and magnetic, non-convulsive, and convulsive approaches. This review discusses the state-of-the-science surrounding promising avenues of NIBS currently in pre-approval stages for non-affective psychiatric disorders. We consider emerging therapies for psychosis, anxiety disorders, obsessive-compulsive disorder, and borderline personality disorder, utilizing transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and magnetic seizure therapy (MST), with an additional brief section for early-stage techniques including transcranial focused ultrasound stimulation (tFUS) and transcranial alternating current stimulation (tACS). As revealed in this review, there is considerable promise across all four psychiatric indications with different NIBS approaches. Positive findings are notable for the treatment of psychosis using tDCS, MST, and rTMS. While rTMS is already FDA approved for the treatment of obsessive-compulsive disorder, methodologies such as tDCS also demonstrate potential in this condition. Emerging techniques show promise for treating non-affective disorders likely leading to future regulatory approvals.

Altered levels of cytokine, T- and B-lymphocytes, and PD-1 expression rates in drug-naïve schizophrenia patients with acute phase

Many studies have investigated the changes of immune cells and proinflammatory cytokines in patients with acute schizophrenia, but few studies have investigated the functional phenotypes of immune cells and the expression rate of programmed cell death protein 1 (PD-1)/ programmed cell death-Ligand 1 (PD-L1). The aim of this study was to investigate the extent of immune cells activation, PD-1/PD-L1 expressions, and altered cytokine levels in drug-naïve schizophrenia patients with acute-phase. 23 drug-naïve schizophrenia patients in acute-phase and 23 healthy individuals were enrolled in this study as experimental and control groups, separately. Socio-demographic information including gender, age, duration of illness, and smoking status was collected for each subject. Beckman DXFLEX triple laser thirteen-color flow cytometer and self-contained software CytoFLEX flow cytometric analysis software were used to detect the expressions of PD-1/PD-L1 on CD4+/CD8+ T lymphocytes, B lymphocytes, monocytes and NK cells. BD Bioscience was used to examine the levels of cytokines including interferon (IFN)-γ, tumor necrosis factor (TNF)-α, Interleukin (IL)-2, IL-4, IL-6, and IL-10. Drug-naïve schizophrenia patients in acute-phase had higher levels of peripheral blood CD4+ T lymphocytes and B lymphocytes, higher PD-1 expression in B lymphocytes, and lower levels of CD8+ T lymphocytes. In addition, IL-6 levels of peripheral blood were higher in schizophrenia patients (all P < 0.05). Significant immune stress was present in schizophrenia patients with acute-phase.

A multicenter, double-blind, randomized, controlled study of patients with treatment-resistant schizophrenia treated with yokukansan for 12 weeks

Aim

We conducted a 12-week double-blind, placebo-controlled, multicenter study to evaluate the efficacy and safety of yokukansan in patients with schizophrenia.

Methods

Patients with schizophrenia resistant to antipsychotics whose Positive and Negative Syndrome Scale (PANSS) scores were stable within five points were enrolled and assigned to the yokukansan or placebo group. Fifty-three of the 61 consenting patients were allocated to the yokukansan (n = 27) and placebo (n = 26) groups.

Results

The changes in total and positive PANSS scores at 12 weeks were significantly greater in the yokukansan group than in the placebo group. There were no significant changes in other psychiatric symptom rating scores in either group. Adverse reactions were reported in six of 27 patients (22.2%) in the yokukansan group and five of 26 patients (19.2%) in the placebo group, all of which were nonserious.

Conclusion

Yokukansan is very safe and has clinical potential as a treatment for schizophrenia in combination with Western medicine.

The Challenge of Managing Refractory Psychosis Amid Multiple Medication Side Effects: A Case Report and Review of the Literature

Antipsychotics are the mainstay for the treatment of schizophrenia and other psychotic disorders; however, these agents are associated with an extensive side effect profile that may complicate treatment outcomes. We present the case of a 35-year-old woman with a history of schizoaffective disorder and five prior psychiatric hospitalizations. The patient first presented to the hospital for disorganized behavior, in addition to poor sleep, auditory hallucinations, and racing thoughts in the context of medication nonadherence. She received two loading doses of intra-muscular paliperidone with fair symptomatic improvement. After discharge, she was scheduled to receive a monthly dose of paliperidone, which she missed, resulting in decompensation, re-emergence of psychosis, and another hospitalization two months later. She was given the missed dose with no improvement and progressive deterioration, for which alternative agents were tried. She received olanzapine and was tried briefly on quetiapine and haloperidol as well, with no benefit, and she also developed abnormal perioral movements. She was reloaded with paliperidone, and her psychotic symptoms improved, although she developed akathisia and hyperprolactinemia. The patient returned to the hospital two days later after being discharged, due to disorganized behavior and multiple delusions. Clozapine was started and titrated to 100 mg qam and 200 mg qhs. While on clozapine, she developed profuse sialorrhea that was treated with sublingual atropine drops, and by the time of discharge psychotic symptoms had markedly improved, perioral movements diminished, and prolactin level trended down. The patient maintained stability for over a year after the last admission. Identifying antipsychotics to successfully treat refractory psychosis and managing their multiple potential side effects is challenging but can result in better quality of life for patients as well as improved treatment adherence. This case report is unique in the way it illustrates this point, while discussing different approaches to managing multiple side effects that can happen simultaneously.

Oleanolic acid alleviates the extrapyramidal symptoms and cognitive impairment induced by haloperidol through the striatal PKA signaling pathway in mice

Haloperidol, one of the representative typical antipsychotics, is on the market for schizophrenia but shows severe adverse effects such as extrapyramidal symptoms (EPS) or cognitive impairments. Oleanolic acid (OA) is known to be effective for tardive dyskinesia which is induced by long-term treatment with L-DOPA. This study aimed to investigate whether OA could ameliorate EPS or cognitive impairment induced by haloperidol. The balance beam, catalepsy response, rotarod and vacuous chewing movement (VCM) tests were performed to measure EPS and the novel object recognition test was used to estimate haloperidol-induced cognitive impairment. Levels of dopamine and acetylcholine, the phosphorylation levels of c-AMP-dependent protein kinase A (PKA) and its downstream signaling molecules were measured in the striatum. OA significantly attenuated EPS and cognitive impairment induced by haloperidol without affecting its antipsychotic properties. Valbenazine only ameliorated VCM. Also, OA normalised the levels of dopamine and acetylcholine in the striatum which were increased by haloperidol. Furthermore, the increased phosphorylated PKA, extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB) levels and c-FOS expression level induced by haloperidol were significantly decreased by OA in the striatum. In addition, cataleptic behaviour of haloperidol was reversed by sub-effective dose of H-89 with OA. These results suggest that OA can alleviate EPS and cognitive impairment induced by antipsychotics without interfering with antipsychotic properties via regulating neurotransmitter levels and the PKA signaling pathway in the striatum. Therefore, OA is a potential candidate for treating EPS and cognitive impairment induced by antipsychotics.

Antipsychotics: 70 Years

To Davide [...].

Chronic Deep Brain Stimulation of the Human Nucleus Accumbens Region Disrupts the Stability of Intertemporal Preferences

When choosing between rewards that differ in temporal proximity (intertemporal choice), human preferences are typically stable, constituting a clinically relevant transdiagnostic trait. Here we show, in female and male human patients undergoing deep brain stimulation (DBS) of the anterior limb of the internal capsule/NAcc region for treatment-resistant obsessive-compulsive disorder, that long-term chronic (but not phasic) DBS disrupts intertemporal preferences. Hierarchical Bayesian modeling accounting for temporal discounting behavior across multiple time points allowed us to assess both short-term and long-term reliability of intertemporal choice. In controls, temporal discounting was highly reliable, both long-term (6 months) and short-term (1 week). In contrast, in patients undergoing DBS, short-term reliability was high, but long-term reliability (6 months) was severely disrupted. Control analyses confirmed that this effect was not because of range restriction, the presence of obsessive-compulsive disorder symptoms or group differences in choice stochasticity. Model-agnostic between- and within-subject analyses confirmed this effect. These findings provide initial evidence for long-term modulation of cognitive function via DBS and highlight a potential contribution of the human NAcc region to intertemporal preference stability over time.SIGNIFICANCE STATEMENT Choosing between rewards that differ in temporal proximity is in part a stable trait with relevance for many mental disorders, and depends on prefrontal regions and regions of the dopamine system. Here we show that chronic deep brain stimulation of the human anterior limb of the internal capsule/NAcc region for treatment-resistant obsessive-compulsive disorder disrupts the stability of intertemporal preferences. These findings show that chronic stimulation of one of the brain's central motivational hubs can disrupt preferences thought to depend on this circuit.

Selected neuroendocrine factors as potential molecular biomarkers of early non-affective psychosis course in relation to treatment outcome: A pilot study

The aim of this pilot study was to find whether the dysregulation of neuroendocrine biomarker signaling pathways in the first episode of non-affective psychosis is a predictive factor of treatment outcome. Patients with the first episode of non-affective psychosis (N = 29) were examined at admission, at discharge, and at follow-up (N = 23). The biomarkers included serum aldosterone, cortisol, free thyroxine, thyroid stimulating hormone, and prolactin. We revealed lower baseline aldosterone and higher baseline cortisol concentrations in patients with very good outcome compared to those with good outcome after one year. We failed to reveal any significant association between treatment outcome and neurohumoral biomarkers in the whole sample at 1-year follow-up. However, baseline aldosterone concentrations negatively correlated with total PANSS scores at the discharge. Lower baseline aldosterone and higher baseline cortisol concentrations have the potential to predict a more favorable outcome for patients with the first episode of psychosis.

The Influence of Electroconvulsive Therapy (ECT) on Brain-Derived Neurotrophic Factor (BDNF) Plasma Level in Patients with Schizophrenia-A Systematic Review and Meta-Analysis

The main aim of this systematic review and meta-analysis is to establish whether there is a correlation between the brain-derived neurotrophic factor (BDNF) level and electroconvulsive therapy (ECT) treatment and the reduction in psychotic symptoms in patients diagnosed with schizophrenia. A systematic search of PubMed/Medline, Cochrane Library, Web of Science, Scopus and Embase was conducted up to March 2023. Inclusion criteria: studies in which adult patients with schizophrenia treated with antipsychotic medication received ECT therapy and had the BDNF level measured before and after ECT treatment. Exclusion criteria: animal and in vitro studies or studies not involving complete information about the treatment and concentration of BDNF in plasma. The risk of bias was assessed using Egger's regression-based test for meta-analysis with continuous outcomes. Six studies comprising 248 individuals with schizophrenia were included. A statistically significant increase in BDNF levels after ECT treatment was observed only in two studies (p < 0.001 and p < 0.027, respectively), whereas in four other studies, an upward trend without statistical significance was noticed. The estimated overall size effect revealed that ECT therapy caused a slight change in the BDNF level but without statistical significance (ES = -0.328). Different numbers of ECT procedures (4-10), final measurement of the BDNF level made at a different time point, using bilateral or unilateral electrode positioning during ECT and treatment with different combinations of typical or atypical antipsychotic medications may be potential reasons for the lack of statistical significance in the changes in BDNF levels after treatment. Data regarding the measurement of BDNF levels pre and post ECT therapy in patients with schizophrenia are very limited without an extended follow-up period and evaluation of mental health change. Our meta-analysis showed that treatment with ECT therapy and antipsychotic medication increases serum BDNF levels in patients with drug-resistant schizophrenia compared to patients treated with medication only; however, this effect is not statistically significant.

Novel pharmacotherapy targeting the positive symptoms of schizophrenia

INTRODUCTION

The severity of positive symptoms in schizophrenia is associated with poor prognosis. About one-third of schizophrenia patients partially respond to treatment with available antipsychotics. The purpose of the present manuscript is to provide an updated overview of novel pharmacotherapy targeting positive symptoms in schizophrenia.

AREAS COVERED

A comprehensive research on the main database sources (PubMed, PsychINFO, Isi Web of Knowledge, MEDLINE, and EMBASE) was performed to obtain original articles published till 31st January 2023 about new pharmacological strategies for the treatment of positive symptoms in schizophrenia.

EXPERT OPINION

The most promising compounds include: lamotrigine, pro-cognitive-compounds (donepezil - in the short term, idazoxan and piracetam) and drugs acting partially or totally outside the Central Nervous System (CNS) (anti-inflammatory drugs: celecoxib, methotrexate; cardiovascular compounds: L-theanine, mononitrate isosorbide, propentofylline, sodium nitroprusside; metabolic regulators: diazoxide, allopurinol; others: bexarotene, raloxifene [in women]). The effectiveness of the latter compounds indicates that other biological systems, such as immunity or metabolism can be object of future research to identify pharmacological targets for positive symptoms of schizophrenia. Mirtazapine could be useful for treating negative symptoms without increasing the risk of a worsening of delusions/hallucinations. Nevertheless, the lack of replication of studies prevents to draw definitive conclusions and future studies are needed to confirm the findings presented in this overview.

Phase 2 Results Indicate Evenamide, A Selective Modulator of Glutamate Release, Is Associated With Clinically Important Long-Term Efficacy When Added to an Antipsychotic in Patients With Treatment-Resistant Schizophrenia

Results from a pilot, 6-week, randomized, open-label, rater-blinded study, with 46-week extension, indicate very good tolerability with exceptional, clinically important, increasing efficacy of evenamide (7.5, 15, and 30 mg bid), a glutamate modulator, as add-on treatment to antipsychotics in 161 treatment-resistant, schizophrenia patients. Ninety-five percent of patients completed 6 weeks (1 discontinued for adverse event), and 89% continued in the extension. Results from the first 100 patients enrolled showed very low attrition over 1 year (77 completers); data pooled from all dose groups showed the Positive and Negative Syndrome Scale total score improved significantly (P < .001; paired t test; last observation carried forward [LOCF]) from baseline at 6 weeks (-9.4), 6 months (-12.7), and 1 year (-14.7); similarly, the proportion of responders (≥20% improvement) increased over time from 6 weeks (16.5%) to 6 months (39%) to 1 year (47.4%). Noteworthy improvement was also observed at each timepoint on the Clinical Global Impression - Severity scale and Clinical Global Impression of Change, indicating progressively increasing efficacy of evenamide up to 1 year.

Augmentation Therapies as Treatments for Coexisting Somatic Problems in Schizophrenia-A Systematic Review

The aim of this review is to appraise the data from available randomized clinical trials (RCT) regarding the possible combinations of neuroleptic and non-antipsychotic treatment which could enhance antipsychotic therapy efficacy whilst simultaneously addressing somatic symptoms in individuals with schizophrenia. A systematic search of the PubMed database up to February 2022 was conducted. Inclusion criteria: randomized controlled trials using augmentation therapy in chronic schizophrenia in adults, written in English, and only studies with psychometric assessments of schizophrenia were incorporated. Exclusion criteria: non-clinical, first episode of schizophrenia, patients on medication other than antipsychotics augmented, and not adjunctive therapy. Overall, 37 studies of 1931 patients with schizophrenia who received a combination of antipsychotic medication with other drugs were selected. A statistically significant reduction of negative and positive symptoms of schizophrenia, measured with the PANSS scale, when using a combination of antipsychotic treatment along with aspirin, simvastatin, N-acetylcysteine, or pioglitazone was found. A combination of antipsychotic medication with aspirin, simvastatin, N-acetylcysteine, or pioglitazone seems to be effective in the reduction of symptoms of schizophrenia in adults, but long-term studies are required to confirm this effect.

Exploration of the role of emotional expression of treatment-resistant schizophrenia patients having followed virtual reality therapy: a content analysis

BACKGROUND

Emotional responses are an important component of psychotherapeutic processes. Avatar therapy (AT) is a virtual reality-based therapy currently being developed and studied for patients suffering from treatment resistant schizophrenia. Considering the importance of identifying emotions in therapeutical processes and their impact on the therapeutic outcome, an exploration of such emotions is needed.

METHODS

The aim of this study is to identify the underlying emotions at the core of the patient-Avatar interaction during AT by content analysis of immersive sessions transcripts and audio recordings. A content analysis of AT transcripts and audio recordings using iterative categorization was conducted for 16 patients suffering from TRS who underwent AT between 2017 and 2022 (128 transcripts and 128 audio recordings). An iterative categorization technique was conducted to identify the different emotions expressed by the patient and the Avatar during the immersive sessions.

RESULTS

The following emotions were identified in this study: Anger, Contempt/ Disgust, Fear, Sadness, Shame/ Embarrassment, Interest, Surprise, Joy and Neutral. Patients expressed mostly neutral, joy and anger emotions whereas the Avatar expressed predominantly interest, disgust/contempt, and neutral emotions.

CONCLUSIONS

This study portrays a first qualitative insight on the emotions that are expressed in AT and serves as a steppingstone for further investigation in the role of emotions in the therapeutic outcomes of AT.

Association Between Clozapine Plasma Concentrations and Treatment Response: A Systematic Review, Meta-analysis and Individual Participant Data Meta-analysis

BACKGROUND AND OBJECTIVES

Although therapeutic drug monitoring of clozapine is recommended, its optimisation is often adjusted only on the basis of dosage. The aim of this study was to assess the link between clozapine plasma concentrations and clinical response by a meta-analysis of published studies and by an individual participant data meta-analysis.

METHODS

We conducted a computerised search of bibliographic databases (EMBASE, PubMed, Clinical Trials, and Web of Science) to identify studies that assessed the relationship between clozapine serum or plasma concentrations and clinical efficacy. Using pooled data, we investigated the association between improvement of clinical outcome and clozapine or norclozapine plasma concentrations, the sum of clozapine and norclozapine plasma concentrations, and the coefficient of variation of clozapine plasma concentrations. Using available individual data, we assessed the relationship between clozapine plasma concentrations and clinical response (changes in the Brief Psychiatric Rating Scale score) and identified a threshold level for a favourable clinical response.

RESULTS

Fifteen studies satisfied inclusion criteria. Our meta-analysis showed that responders had clozapine plasma concentrations that were, on average, 117 ng/mL higher than non-responders. The patients with plasma clozapine concentrations above the thresholds identified in each study had a higher likelihood of responding (odds ratio = 2.94, p < 0.001). Norclozapine plasma concentrations were not associated with a clinical response. The meta-analysis of individual data supported this result and confirmed the link between clozapine concentrations and a change in the Brief Psychiatric Rating Scale score and/or the probability of clinical response. Finally, with the analysis of the coefficient of variation of clozapine plasma concentrations, we found that a greater inter-individual fluctuation in plasma concentrations was associated with a loss of clinical response.

CONCLUSIONS

Our work confirmed that, in contrast to clozapine doses, clozapine plasma concentrations were related to a favourable clinical response, with a mean difference between responders and non-responders of 117 ng/mL. A threshold for a treatment response of 407 ng/mL was determined, with a high discriminatory capacity, and a sensitivity and specificity of 71% and 89.1%, respectively.

Towards Novel Potential Molecular Targets for Antidepressant and Antipsychotic Pharmacotherapies

Depression and schizophrenia are two highly prevalent and severely debilitating neuropsychiatric disorders. Both conventional antidepressant and antipsychotic pharmacotherapies are often inefficient clinically, causing multiple side effects and serious patient compliance problems. Collectively, this calls for the development of novel drug targets for treating depressed and schizophrenic patients. Here, we discuss recent translational advances, research tools and approaches, aiming to facilitate innovative drug discovery in this field. Providing a comprehensive overview of current antidepressants and antipsychotic drugs, we also outline potential novel molecular targets for treating depression and schizophrenia. We also critically evaluate multiple translational challenges and summarize various open questions, in order to foster further integrative cross-discipline research into antidepressant and antipsychotic drug development.

Potassium channel modulators and schizophrenia: an overview of investigational drugs

INTRODUCTION

Schizophrenia is severe mental illness comprised of positive, negative, and cognitive symptoms. Existing pharmacologic options exert their actions on the dopamine receptor but are largely ineffective at treating negative and cognitive symptoms. Alternative pharmacologic options that do not act directly on the dopamine receptor are being investigated, including potassium channel modulators. It has been hypothesized that dysfunctional fast-spiking parvalbumin-positive GABA interneurons, regulated by Kv 3.1 and Kv 3.2 potassium channels, contribute to the symptoms of schizophrenia, making potassium channels an area of clinical interest.

AREAS COVERED

This review will highlight potassium channel modulators for the treatment of schizophrenia, with a focus on AUT00206. Background on Kv3.1 and Kv3.2 potassium channels will be explored. Our search strategy included a literature review utilizing PubMed, Clinicaltrials.gov, and sources available on the manufacturer's website.

EXPERT OPINION

Initial data on potassium channel modulators is promising, however, further study is needed, and existing evidence is limited. Early data suggests that dysfunctional GABA interneurons can be ameliorated through modulators of Kv3.1 and Kv3.2 channels. AUT00206 has been shown to improve dopaminergic dysfunction induced by ketamine and PCP, improve resting gamma power in patients with schizophrenia, impact dopamine synthesis capacity in a subgroup of individuals with schizophrenia, and affect reward anticipation-related neural activation.

Efficacy of transcutaneous electrical acupoint stimulation for patients with first-episode schizophrenia: An 8-week, preliminary, randomized controlled trial

Combination therapy with antipsychotics has been investigated for treating schizophrenia, and has shown clear advantages among non-invasive therapies. Transcutaneous electrical acupoint stimulation (TEAS) is a novel non-invasive treatment with definite efficacy in treating mental disorders. The current study aimed to investigate the efficacy of TEAS in further improving the psychotic symptoms in patients with first-episode schizophrenia (FES) being treated with pharmacological drugs. This 8-week, preliminary, sham-controlled, randomized clinical trial was conducted in patients with FES to compare the efficacy of TEAS and sham TEAS in combination with aripiprazole treatment. The primary outcome was a change in the Positive and Negative Syndrome Scale (PANSS) score after ending the intervention (Week 8). A total of 49 participants completed the whole treatment cycle. The linear mixed-effects regression for PANSS indicated a significant time × group interaction (F(2, 116)=9.79, p <0.001). The PANSS score differed by 8.77 points (95% CI, -2.07 to -15.47 points; p=.01) between the TEAS group and the sham TEAS group after 8 weeks of treatment; this difference was significant. This study indicates that 8 weeks of TEAS combined with aripiprazole treatment can effectively treat FES. Thus, TEAS is an effective combination therapy to improve the psychiatric symptoms of FES.